How to have a value passed to scope from outside the controller? - javascript

I am new to angular world and I have function which is loading the html inside perticular div on load and then controller gets initialize. I want to make single var available inside the controller so wondering if it's possible to assign that var to scope from outside the controller.
//controller
var cntlrs = angular.module('MyModule');
cntlrs.controller('ControllerTest', function ($scope, $http) {
//want to have var available here from $scope
});
//accessing scope from outside
var appElmt = document.querySelector('[ng-app=MyApp]');
var $scope = angular.element(appElmt).scope();
var customer = "New Customer";
//how can I set customer value inside scope?

I would suggest reading the angular docs more. $scope is your model (or probably the term ViewModel is more appropriate).
To get values into your controller, I would recommend a factory or a service. One can call setCustomer on the factory, then other controllers would be able to see that value using getCustomer.
var mod = angular.module('MyModule', []);
mod.factory("CustomerFactory", function () {
var customer;
return {
getCustomer: function () {
return custData;
}
setCustomer: function (custData) {
customer = custData;
}
}
});
mod.controller("TestController", function ($scope, $http, CustomerFactory) {
$scope.customer = CustomerFactory.getCustomer();
}
It might also be better if you weren't referencing $scope outside of angular (i.e. from angular.element(...).scope()). I don't know what you are trying to solve, but it seems like from the code above, all that logic can be put inside the controller.

Yes, from outside the controller you can target an element that is within your angular controller:
var scope = angular.element("#YourElementID").scope();
And now you will have access to everything on the scope (Just as if you were using $scope)

I decided to work like this, and it seems to be allright!! It does not require a big effort, the only boring part is that in the template you need always to use vars.somepropertyormethod
//an outside var that keeps all the vars I want in my scope
var vars = {
val1: 1,
val2: "dsfsdf",
val3: function() {return true;}
}
//and here I set the controller's scope to have ONLY vars and nothing else:
angular.module('myModule', [])
.controller('myControllerOpenToTheWorld', function($scope) {
$scope.vars = vars;
});
With this, I can set vars.anyproperty from anywhere I want. The trick is that the real values are all wrapped inside an object, so as long as you don't reassign the wrapper vars, you can access it from both outside and inside:
//change val2
vars.val2 = "new value changed from outside";
In the markup, it would work like this:
<div>{{vars.val1}}</div>
<div ng-if:"vars.val3()">{{vars.val2}}</div>

Related

Testing javascript functions - that are not visible to controller (angular)

I am using the controller as syntax from angular and i want to test my code using jasmine and sinon.
Let's say i want the following controller code :
angular
.module('Test')
.controller('TestController', TestController);
TestController.$inject = [];
function TestController() {
var viewModel = this;
viewModel.myFunction = myFunction;
function myFunction(){
//do something
//now call a helper function
helperFunction()
}
function helperFunction(){
// ....
}
}
My question is how i can test the helperFunction() or even put a spy on it ? My helper is not visible in my test.
Here is my test :
(function () {
'use strict';
var myController;
describe('Test', function () {
beforeEach(module('Test'));
beforeEach(inject(function ($controller, $injector) {
myController = $controller('TestController');
}));
it('Tests helperFunction', function (){
var sinonSpy = sinon.spy(myController, 'helperFunction');
//perform the action
myController.myFunction();
//expect the function was called - once
expect(sinonSpy .callCount).toEqual(1);
}
})
})
You cannot have access to those functions. When you define a named JS function it's the same as saying:
var helperFunction = function(){};
In which case it would be pretty clear to see that the var is only in the scope within the block and there is no external reference to it from the wrapping controller.
To make a function testable, you need to add it to the $scope of the controller.
viewModel.helperFunction = helperFunction;
But be aware that is not a good idea to be exposing everything just to make it testable. You really need to consider if testing it will actually add some value to your project
try to do so :
var vm = controller("helperFunction", { $scope: scope });
and then:
vm.myFunction();
Add the following code into your controller:
angular.extend($scope, {
helperFunction:helperFunction
});

Access controller property from another Class in AngularJS

today I discovered the following problem while using AngularJS.
My Code is as follows:
app.controller("SomeController", function(){
this.foo = true
this.changeFoo = function(bool){
this.foo = bool
}
api.check(function(response){
this.changeFoo(response.bar)
})
})
(by the way: response & response.bar are not undefined)
api is an instance of my class API, defined outside of my Angular-code.
The problem is, that I can not change this.foo inside my callback-function.
What can I do to access this.foo?
Edit:
I tried to pass this as an argument, the result is the same
api.check(this, function(scope, response){
scope.foo = response.bar
})
scope seems to be defined inside this function, but the changes doesn't effect anything
You need to assign this to a different variable in your angular code before your Api call. Then use that variable to access your this variable. Like this
app.controller("SomeController", ['$scope',function($scope){
this.foo = true;
this.changeFoo = function(bool){
this.foo = bool;
$scope.$apply();
};
Var controller=this;
api.check(function(response){
controller.changeFoo(response.bar);
});
}]);

How to inject variable into controller

I am trying to get started with angular.js but I can't figure out how to inject a simple variable into my controller before testing.
This is my controller:
angular.module("app").controller("SimpleController", SimpleController);
function SimpleController() {
var vm = this;
vm.myVar = 1;
vm.getMyVar = function() {
return vm.myVar;
};
}
My test looks like the following:
describe("SimpleController", function() {
var vm;
beforeEach(module('app'));
beforeEach(inject(function($controller, $rootScope) {
vm = $controller('SimpleController', {
$scope: $rootScope.$new(),
myVar: 2
});
}));
it('myVar should be 2 not 1', function() {
expect(vm.getMyVar()).toEqual(2);
});
});
I did a lot of google searching but this is really confusing because many people do use $scope in controller and not thisas I do. But I guess the injection of variables should work with this too?
You may want to try writing your controller this way. This will make $scope accessible.
(function () {
angular.module("app").controller("SimpleController", SimpleController);
SimpleController.$inject = ['$scope'];
function SimpleController($scope) {
$scope.somevar = "something";
}
})();
I'm sure you've probably came across the documentation, but here is a link to the docs which contains the basics and should at least get you going in the right direction.
Another alternative would be something like this:
app.controller('SimpleController', ['$scope', function($scope) {
$scope.somevar = "something";
....
}]);
When you use $scope, you're making that property publicly available in the view.

How can i pass scope in template in angular js

I have one BaseController with common functions which my all other controllers inherit .
The controller is like this
function BaseController () {
this.defaultFilters = {};
this.doStuff = function ($scope) {
$scope.myobj.value = 1;
this.otherfunction();
};
I inherit that in my controller like this
BaseController.call($scope);
Now in my do stuff function i need to pass $scope because myobj is only visible there.
Now i want to know that how can i pass that in my template because i want to call that function when some click on some button
ng-click="doStuff(scope)"
Everything that you associate with your controller's scope, so you just associate your scope with some variable and i guess that will do the job.
Something like this :
app.controller(function($scope) {
$scope.scope = $scope;
});
But if you go by some standard approach, i suggest moving these common functions inside some service, injecting this service into each controller and using it in the views.
Something like this :
app.service("constantService", function() {
this.data = {}; // This will represent your common data.
this.commonFunction = function() {
};
});
app.controller(function() {
$scope.constantService = constantService;
// You can now use $scope.constantService.data as your reference for data, and then can copy it to some local $scope variable whenever required.
});
ng-click="constantService.commonFunction()"

http.jsonp and callbacks in javascript

I am working on a calculator that will consider AWS instance costs. I am pulling the data from a .js file on amazon and I would like to read it into an object but i keep getting an error "Uncaught ReferenceError: callback is not defined" .. here is my .js file.
(function() {
var app = angular.module('formExample', []);
var ExampleController = function($scope, $http) {
$scope.master = {};
$scope.update = function(user) {
$scope.master = angular.copy(user);
$scope.GetAws();
};
$scope.reset = function() {
$scope.user = "";
};
function callback(data) {
$scope.aws = data;
}
$scope.GetAws = function() {
var url = "http://a0.awsstatic.com/pricing/1/ec2/linux-od.min.js?callback=callback";
$http.jsonp(url);
};
$scope.reset();
};
app.controller('ExampleController', ['$scope', '$http', ExampleController]);
}());
It is weird that the aws link you are using supports jsonp but it does not take custom callback function name. (Atleast you can look up to find out if the query string they are looking for is callback or not). angular handles it when we provide callback=JSON_CALLBACK it gets translated to angular.callbacks_x which are exposed globally temporarily by angular to handle the request and resolve the promise accordingly. But for this the endpoint must take the callback argument and wrap the response in the same string and function invocation. However this endpoint does not seem to consider it and even without any callback it automatically wraps into default callback function invocation. So you would need to inject $window (Correct DI way) object and set callback function to it and ?callback=callback is irrelevant.
var ExampleController = function($scope, $http, $window) {
$scope.master = {};
//....
$window.callback = function(data) {
$scope.aws = data;
}
$scope.GetAws = function() {
var url = "http://a0.awsstatic.com/pricing/1/ec2/linux-od.min.js?callback=callback";
$http.jsonp(url);
};
$scope.reset();
};
app.controller('ExampleController', ['$scope', '$http', '$window', ExampleController]);
Plnkr
It is because the AWS script is looking to call a function called "callback" on the global scope (outside of Angular). Since your function is within the scope of another (IIFE) function, it cannot be accessed.
What I've done in a case like this is simply put the function in the global scope.
In cases where an application requires some API to have loaded before Angular can do it's magic and has a callback similar to your situation, I have done the following, manually bootstrapping Angular:
index.html
<script src="http://www.example.com/api?callback=myCallbackFunction"></script>
app.js
// callback function, in global (window) scope
function myCallbackFunction() {
// manually bootstrap Angular
angular.element(document).ready(function() {
angular.bootstrap(document, ['myApp']);
});
}
// your IIFE
(function() {
})();
Notice callback should be set in window scope.
So,one solution is like:
$scope.reset = function() {
$scope.user = "";
};
window.callback = function(data) {
$scope.aws = data;
}
$scope.GetAws = function() {
var url = "http://a0.awsstatic.com/pricing/1/ec2/linux-od.min.js?callback=callback";
$http.jsonp(url);
};

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